Search Results (128)

Prometryn and acetochlor are herbicides used to control weeds in farmlands and other areas. They enter the soil through direct application, residual accumulation in crops, and atmospheric deposition. The pollution of their residues in the environment has attracted people’s attention. Bioremediation is one of the main methods to solve such problems. In this study, the effects of prometryn and acetochlor-degrading strain NM-1 on soil enzymes, soil microbial communities, and physiological indexes of soybean seedlings during soil remediation were studied, and the relationship between them was discussed. The results showed that 81.54% of prometryn (50 mg·L⁻¹) and 89.47% of acetochlor (50 mg·L⁻¹) were degraded within 15 days after NM-1 inoculation in soil. NM-1 positively affected soil enzyme activities and soil microbial communities, and the abundance of beneficial bacteria in soil increased. More importantly, the inoculation of strain NM-1 under prometryn and acetochlor stress significantly increased plant height, root length, root volume, water content, chlorophyll concentration, and root activity of soybean. The results of these studies showed that the NM-1 strain showed significant potential in bioremediation in order to provide technical support for solving the problem of prometryn and acetochlor pollution. Full article

This study aims to improve the understanding of, and provide insights into, the environmental fate of herbicides currently used in agriculture, which is addressed through the analysis of the quality of canal water used for irrigation and the agricultural soil in the immediate vicinity. The research was conducted in the main agricultural region of Serbia, characterized by intensive crop production in conventional agriculture. Monitoring was focused on the Danube–Tisza–Danube canal system, specifically the Bogojevo–Bečej section. The presence of 41 currently used herbicides was analyzed in 520 soil samples collected from two depths (0–30 cm and 30–60 cm), as well as in 100 canal water samples. Results showed a high frequency of clopyralid, 2,4-D-methyl ester, terbuthylazine, fenoxaprop-ethyl, and aclonifen, with the highest amountsbeingterbuthylazine and quizalofop-ethyl, which was possibly a consequence of their recent application shortly before sampling. Concentrations of herbicide residues at different depths were closely similar, without the impact of soil mechanical and chemical characteristics on herbicide levels. In canal water characterized as moderately salty and slightly alkaline, herbicide residues were far below the maximum allowable concentrations, suggesting that the canal water is suitable for aquatic life, irrigation, and other uses. The findings suggest that the appropriate use of herbicides in regions under intensive agriculture is important for reducing environmental contamination. Full article

Pesticide residues pose risks to the environment and human health. Little is known about how tillage and straw management affect herbicide behavior in soil. This study investigated the effects of different tillage practices under varying straw incorporation scenarios on the degradation of five commonly used herbicides in a long-term experimental field located in the maize belt of Siping, Jilin Province. Post-harvest soil samples were analyzed for residual herbicide concentrations and basic soil physicochemical properties. A human health risk assessment was conducted, and a controlled incubation experiment was carried out to evaluate herbicide degradation dynamics under three management systems: straw incorporation with traditional rotary tillage (ST), straw incorporation with strip tillage (SS), and no-till without straw (CK). Residual concentrations of atrazine ranged from not detected (ND) to 21.10 μg/kg (mean: 5.28 μg/kg), while acetochlor showed the highest variability (2.29–120.61 μg/kg, mean: 25.26 μg/kg). Alachlor levels were much lower (ND–5.71 μg/kg, mean: 0.34 μg/kg), and neither nicosulfuron nor mesotrione was detected. Soil organic matter (17.6–20.89 g/kg) positively correlated with available potassium and acetochlor residues. Health risk assessments indicated negligible non-cancer risks for both adults and children via ingestion, dermal contact, and inhalation. The results demonstrate that tillage methods significantly influence herbicide degradation kinetics, thereby affecting environmental persistence and ecological risks. Integrating straw with ST or SS enhanced the dissipation of atrazine and mesotrione, suggesting their potential as effective residue mitigation strategies. This study highlights the importance of tailoring tillage and straw management practices to pesticide type for optimizing herbicide fate and promoting sustainable agroecosystem management. Full article

Diuron (DU) is a widely used phenylurea herbicide designed to inhibit weed growth, but its high toxicity and prolonged half-life contribute significantly to environmental contamination. The majority of electrochemical (EC) sensors typically rely on a single response signal for the detection of DU, rendering them highly susceptible to interference from variable background noise in complex environments, thereby reducing the selectivity and robustness. By integrating molecularly imprinted polymer (MIP) with a ratiometric strategy, the aforementioned issues could be solved. In this study, a novel signal on-off ratiometric MIP-EC sensor was developed based on the MXene/PEI-MWCNTs nanocomposite for the detection of DU. Positively charged PEI-MWCNTs was used as an interlayer spacer and embedded into negatively charged MXene by a simple electrostatic self-assembly method. This effectively prevented the agglomeration of MXene and enhanced its electrocatalytic performance. The MIP was synthesized via electropolymerization with DU serving as the template molecule and the selectivity was enhanced by leveraging the gate effect of MIP. Subsequently, a ratiometric MIP-EC sensor was designed by introducing [Fe(CN)₆]^3−/4− into the electrolyte solution as an internal reference. Additionally, the current ratio signal (I_DU/I_[Fe(CN)6]^3−/4−) and DU concentration exhibited a good linear relationship within the range of 0.1 to 100 µM, with a limit of detection (LOD) of 30 nM (S/N = 3). In comparison with conventional single-signal MIP-EC sensing, the developed ratiometric MIP-EC sensing demonstrates superior reproducibility and accuracy. At the same time, the proposed sensor was successfully applied to the quantitative analysis of DU residues in soil samples, yielding highly satisfactory results. Full article

The intensive use of pesticides has raised environmental concerns due to their persistence and slow degradation, posing ecotoxicological risks. Despite regulatory measures, pesticide application remains high, leading to soil and water contamination. To effectively monitor and mitigate these impacts, selecting an appropriate and efficient extraction method for detecting pesticides in soil is critical. This study evaluated the effectiveness of two extraction methods in soil—QuEChERS and QuEChERSER—and assessed the persistence of three commonly used pesticides. A test was conducted using 13 pesticide standards, representing a wide variety of functional groups, to compare the two extraction methods. For the persistence study, a microcosm experiment was performed with three selected pesticides: pendimethalin, oxyfluorfen, and trifloxystrobin. These were chosen due to their agricultural relevance, potential human toxicity, and persistence in various environmental compartments. The impact of two organic amendments on their dissipation was also evaluated. The microcosms were incubated in dark chambers at room temperature for 21 days, and pesticide concentrations were analyzed using ultra-high-performance liquid chromatography–tandem mass spectrometry. Both methods were effective, though performance varied depending on the compound. QuEChERSER proved to be more efficient, requiring less time and fewer resources than the traditional QuEChERS method. Among the three pesticides tested, the herbicide oxyfluorfen was the most persistent, while the fungicide trifloxystrobin showed the least persistence. The application of organic amendments enhanced the dissipation of all three pesticides. These findings highlight the importance of selecting appropriate extraction techniques and adopting sustainable agricultural practices to mitigate pesticide residues in the environment. Full article

A bioassay study was conducted to determine the differences in the sensitivity of selected crops to simulated clomazone residues (nine concentrations were used ranging from 5.625 to 1440 μg a.i./kg soil). White mustard was the most susceptible as measured by shoot fresh weight (SFW) and shoot dry weight (SDW) inhibition, with EC₅₀ values of 94.6 and 128.2 μg a.i./kg soil, respectively. Regarding the EC₅₀ values for the inhibition of pigment content (carotenoids, chlorophyll a and chlorophyll b), sugar beet and white mustard showed a high sensitivity, as the EC₅₀ values for all three pigments were in the range of 45.8–47.4 and 57.5–63.3 μg a.i./kg soil, respectively. However, as the SFW and SDW of sugar beet were only reduced at the three highest clomazone concentrations applied, white mustard proved to be the most sensitive crop. Wheat was less sensitive (EC₅₀ = 214.4–243.8 μg a.i./kg soil, for all three pigments), while sunflower and maize were the least sensitive (EC₅₀ = 359.7–417.5 and 456.1–535.8 μg a.i./kg soil, respectively). Field trials were conducted for two years in the Srem region to study the dynamics of clomazone degradation in sandy loam soil. Clomazone was applied pre-plant incorporated (PPI) and post-emergence (POST-EM) in three doses: 480, 720 and 960 g a.i./ha. Soil samples were taken at regular intervals from the day of herbicide application until one year after application and residue concentrations were determined using the white mustard bioassay (based on the measurement of carotenoid content inhibition). The application rate had no consistent effect on the persistence of clomazone. Slower degradation was observed in the PPI treatment than in the POST-EM treatment (8.5 and 15 days longer average half-lives in the first and second year, respectively). Persistence was affected by lower rainfall, resulting in a longer half-life in the second year (12 days on average). Herbicide residues caused no visible injury to white mustard one year after application, while the reduction in carotenoid content ranged from 0.37 to 22.89%, indicating that no injury can occur to any of the tested crops one year after application of clomazone in sandy loam soil. Full article

Fluridone is a pyrrolidone soil-sealing herbicide that has been widely used in cotton fields in Xinjiang in recent years. The purpose of this study was to establish a method for determining fluridone residues in cotton fields and to perform residue digestion tests, final residue analysis, and dietary risk assessment. Samples were extracted with acetonitrile, purified with primary secondary amine (PSA) and multi-walled carbon nanotubes (MWCNTs), and analyzed by high-performance liquid chromatography (HPLC). The results showed that in a certain concentration range, the concentration and peak area of fluridone showed a good linear relationship (R² > 0.99), with limit of detection (LOD) and limit of quantification (LOQ) values of 0.00090–0.00108 mg·kg⁻¹ and 0.0030–0.0033 mg·kg⁻¹, respectively. The relative standard deviation (RSD) values of fluridone were 0.46% to 4.57% at the spiked level of 0.1, 0.5, and 1.0 mg·kg⁻¹, respectively. The average daily recovery rate of fluridone was 85.08% to 95.07%. The residual levels of fluridone in cottonseed oil were below the safety threshold, indicating no significant dietary risk to consumers. Full article

Mesotrione is a triketone herbicide widely used for weed control in maize (Zea mays L.). In a bioassay conducted under controlled conditions, the simulated residual effects of mesotrione on leafy vegetables, including chard, lettuce, spinach, and endive were evaluated. The herbicide was applied at nine concentrations (0–240 µg a.i./kg soil), with the highest corresponding to the recommended field application rate. Nonlinear regression analysis was used to describe the relationship between morphological (shoot fresh weight) and physiological (pigment content) parameters as a function of herbicide dose. Shoot fresh weight was a more sensitive parameter than pigment content with mean EC₅₀ ± SE values of 23.9 ± 3.5 (chard), 34.3 ± 7.7 (lettuce), 13.2 ± 2.4 (spinach), and 990.3 ± 3921.5 (endive) µg a.i./kg soil, indicating that spinach is the most sensitive and endive the most tolerant species. A mesotrione residue level equivalent to EC₂₀ for shoot fresh weight corresponds to approximately 2, 4, 6, and 29% of the recommended application rate of mesotrione at which spinach, chard, lettuce, and endive (respectively) can be safely sown. Therefore, spinach, chard, and lettuce are not suitable substitutes for maize when the latter fails and should not be sown after silage maize. In such cases, only endive appears to be a viable alternative without the risk of crop injury. Full article

Phytoremediation using Avena sativa offers a sustainable strategy for mitigating sulfentrazone contamination while integrating bioenergy production. This study proposes an analysis of the bioenergy potential and the microbial metagenomic profile associated with Avena sativa in the presence and absence of sulfentrazone, aiming at the synergistic bioprospecting of microbial communities capable of biodegradation and remediation of contaminated environments. Using a randomized block design, we evaluated the bioenergy potential and rhizospheric microbial dynamics of A. sativa in soils with and without sulfentrazone (600 g ha⁻¹). Herbicide residues were quantified via UHPLC-MS/MS, and metagenomic profiles were obtained through 16S rRNA gene and ITS region sequencing to assess shifts in rhizospheric microbiota. Microbial diversity was analyzed using the Shannon and Gini–Simpson Indices, complemented by Principal Component Analysis (PCA). Bioenergy yields (biogas and ethanol) were estimated based on plant biomass. Over 80 days, the cultivation of A. sativa promoted a 19.7% dissipation of sulfentrazone, associated with rhizospheric enrichment of plant growth-promoting taxa (Bradyrhizobium, Rhodococcus, and Trichoderma), which increased by 68% compared to uncontaminated soils. Contaminated soils exhibited reduced microbial diversity (Gini–Simpson Index = 0.7), with a predominance of Actinobacteria and Ascomycota, suggesting adaptive specialization. Despite herbicide-induced stress (39.3% reduction in plant height and 60% reduction in grain yield), the biomass demonstrated considerable bioenergy potential: 340.6 m³ ha⁻¹ of biogas and 284.4 L ha⁻¹ of ethanol. The findings highlight the dual role of A. sativa in soil rehabilitation and renewable energy systems, supported by plant–microbe synergies. Scalability challenges and regulatory gaps in ecotoxicological assessments were identified, reinforcing the need to optimize microbial consortia and implement region-specific management strategies. These results support the integration of phytoremediation into circular bioeconomy models, balancing ecological recovery with agricultural productivity. Future research should focus on microbial genetic pathways, field-scale validation, and the development of regulatory frameworks to advance this green technology in global soil remediation efforts. Full article

The aim of this study is to precisely elucidate the control efficacy of drip irrigation herbicide application against broadleaf weeds and comprehensively assess its safety to cotton. Broadleaf weeds were managed through the application of herbicide in the cotton field. The herbicide was dispensed from a fertilizer tank in tandem with water droplets. A field investigation was conducted via a fixed-point investigation method to assess the herbicide residue levels and the safety of the cotton crop from 2022 to 2023. When 100.8 g a.i./hm² of 48% Flumioxazin SC was applied via drip irrigation, it had no adverse effect on cotton safety at the mature stage. During the fruit-setting stage, it exhibited a significant weeding effect on annual broadleaf weeds such as Solanum nigrum L. and Chenopodium album L. Analysis revealed no pesticide residues in cotton and cottonseeds. Soil pesticide residues were found to be at a low level. The cotton yield reached 5618.1 kg/hm², and the cotton quality met the national standard requirements. For the control of broadleaf weeds in cotton fields, the application of 100.8 g a.i./hm² of 48% Flumioxazin SC via drip irrigation can effectively control broadleaf weeds. This method can suppress annual broadleaf weeds, with S. nigrum and C. album being the dominant weed communities, without compromising the safety and quality of cotton. Although drip irrigation technology offers advantages such as time savings and reduced labor demands, it is essential to adopt appropriate weed control techniques tailored to the specific conditions of different cotton fields. Full article

The results demonstrated that among the total 365 investigated samples, the proportion of samples detecting three target herbicides simultaneously, two herbicides, one herbicide, and none were 0.3%, 6.4%, 65.2%, and 23.2%, respectively. For samples with only one detected herbicide, the detection rates in Jiyuan, Luohe, Puyang, Luoyang, Xuchang, and Hebi were relatively high (ranging from 44% to 100%), whereas those in Sanmenxia, Nanyang, Xinxiang, and Kaifeng were relatively low (ranging from 6% to 20%). Regarding individual herbicides, the detection rates of mesosulfuron-methyl, quinclorac, halosulfuron-methyl, diflufenican, imazethapyr, pyroxasulfone, imazapic, fomesafen, and atrazine were 1.2%, 3.8%, 5.5%, 6.1%, 8.7%, 8.7%, 10.4%, 11.0%, and 33.9%, respectively. Based on these findings, the current reliance on long-acting effect herbicides for weed management in China’s agricultural management practices was systematically analyzed. Within the framework of agricultural sustainability, it is proposed that there is an urgent need to promote the concept of scientific herbicide use among farmers and that pesticide scientists must recognize the extreme importance of continuous innovation and the development of alternative herbicides with new mechanisms of action as a long-term strategic goal. Full article

The residues of the herbicides aminopyralid and iodosulfuron-methyl-sodium are phytotoxic to rotational crops. Their behaviour therefore needs to be studied under different agronomic practises and climatic conditions. The objective of this work was to use controlled laboratory conditions to study the effect of the following: (i) the application of green compost (GC) to agricultural soil, (ii) herbicide dose, (iii) soil moisture, and (iv) soil microbial activity on the degradation rate of aminopyralid and iodosulfuron-methyl-sodium. Moreover, the formation of two iodosulfuron-methyl-sodium metabolites (metsulfuron-methyl and 2-amino-4-methyl-4-methoxy methyl-triazine) and the dissipation mechanism of labelled ¹⁴C-iodosulfuron-methyl-sodium under the same conditions were also studied. Aminopyralid and iodosulfuron-methyl showed slower degradation and half-life values (DT₅₀) that were up to 4.6 and 1.4 times higher, respectively, in soil amended with GC, as the higher organic carbon (OC) content of this soil increased herbicide adsorption. The DT₅₀ values were up to 2.6 and 1.9 times higher for aminopyralid and iodosulfuron-methyl sodium, respectively, in soils treated with the double herbicide dose compared to soils treated with the agronomic dose. The DT₅₀ values for aminopyralid were up to 2.3 times higher in soils with moisture equal to 25% (H25%) of their water-holding capacity (WHC) than in soils with H50%. However, the DT₅₀ values for iodosulfuron-methyl-sodium were slightly lower in soils with H25% than in soils with H50%, due to the formation of bound residues. A biodegradation process significantly contributes to the dissipation of both herbicides. Higher amounts of metabolite metsulfuron-methyl were formed in the GC-amended soil in all cases. The percentages of ¹⁴C extractable in soils treated with both doses of herbicide under H25% were slightly higher than in soils under higher soil moisture (H50%) over time, due to the slower degradation of ¹⁴C-(iodosulfuron-methyl+metabolites). The higher persistence of the herbicides and their metabolites when the doses were applied at a high rate in soil amended with GC and under low moisture content may have negative consequences for the rotational crop. In the case of adverse conditions leading to the persistence of herbicides in the soil during the primary crop, the intervals for crop rotation should be increased. Full article

Citrus is a major crop in the SE US, with groves located primarily in Florida, but adapted cultivars have allowed for the expansion of commercial production into the Coastal Plains region of Georgia. Indaziflam, a cellulose biosynthesis inhibiting residual herbicide, controls numerous grass and broadleaf weed species. Research conducted in Georgia from 2020 to 2022 determined the optimal rate and tree response to indaziflam applications. Biannual treatments applied in April and November in established satsuma citrus groves included residual herbicides indaziflam, flumioxazin, diuron, pendimethalin, simazine, and norflurazon. The data indicated no negative impact on tree diameter growth over 30 months after application initiation. Indaziflam provided residual activity in the first year with >80% weed control for bermudagrass and pink purslane and >70% of cutleaf evening primrose, cutleaf geranium, and wild radish. Greater than 69% of weed control was maintained with indaziflam after sequential application for 2 years. All other herbicides provided inadequate residual weed control. Indaziflam PRE applied in citrus groves in Georgia can provide growers with a reliable herbicide option that has been proven to be safe for trees and season-long weed control. Full article

Corn residual herbicides offer a practical approach to comprehensive weed management throughout the growing season. However, the use of residual pre-emergence herbicides can have a negative impact on crops grown in succession or within a rotation. A study was carried out to determine the effect of the residual activity of selected corn herbicides on soybeans. The objective of the study was to evaluate the impact of these herbicides on the germination of inoculated soybean seeds. Experiments were conducted in greenhouse conditions to check the carryover effect on soybean germination. Treatment combinations of two pre-herbicides and two inoculants were applied: atrazine (2241 g ai ha⁻¹), mesotrione (105 g ai ha⁻¹), and Bradyrhizobium japonicum, Bradyrhizobium japonicum + Bacillus subtilis, respectively. A randomized complete block design evaluated six treatment combinations, including the control. All treatments, except uninoculated treatments, presented efficacy in reducing the carryover effects of corn residual herbicides on the germination of soybeans. An increase in final germination percentage was observed with Bradyrhizobium japonicum + Bacillus subtilis co-inoculation plus atrazine (24% increase) and Bradyrhizobium japonicum plus mesotrione treatment combinations (19% increase). Inoculating soybean seeds with rhizobium bacteria can reduce the carryover effects on the germination of soybean seeds grown in soil applied with atrazine and mesotrione. Full article

Intensive agriculture is the chief cause of soil degradation, particularly in regions with low soil organic carbon status, such as semi-arid southern India. In the quest to attain sustainable yield and improved soil quality, conservation agriculture (CA) is being advocated and adopted globally, including in India. In this experiment, CA was implemented to investigate the synergistic impacts of tillage and weed management on soil quality index and system yield and to identify a remunerative treatment combination that can sustain system yield and enhance soil quality. Contrasting tillage practices (main plots) included the T₁: conventional tillage with cotton–conventional tillage with maize–fallow, i.e., no Sesbania rostrata (Farmers’ practice), T₂: conventional tillage with cotton–zero tillage with maize–zero tillage with Sesbania rostrata and T₃: zero tillage with cotton + Sesbania rostrata residues–zero tillage with maize + cotton residues–zero tillage with Sesbania rostrata + maize stubbles. Weed management tactics (sub-plots) were W₁: chemical weed control, W₂: herbicide rotation, W₃: integrated weed management and W₄: single hand-weeded control in a split-plot design with cotton–maize–Sesbania cropping system over 3 years, in a split-plot design. Principal component analysis (PCA) was performed using the soil quality index (SQI)-CAL Version 1.0 software tool to extract minimum datasets from measured soil properties. A total of 40 soil variables were analyzed at 60 DAS and after the maize harvest, then subjected to principal component analysis (PCA) and subjected to PCA in soil quality index (SQI)-CAL software as to choose variables, minimum dataset and obtain soil quality index. The following soil properties, soil organic carbon (SOC), silt fraction, available soil zinc (Zn), iron (Fe), potassium (K), nitrogen (N), pH, electrical conductivity (EC), soil carbon to nitrogen (C:N) and cation exchange capacity (CEC), were selected as indicators based on correlations, calculated PCA and adept opinions on texture and lime concretions of experimental soil. The soil quality index improved by 23.34% in the T₃W₄ compared to T₁W₁. The system yield was 51.79% higher with the adoption of T₃W₃ compared to T₃W₄ combinations. Therefore, considering both system yield and soil quality index, T₃ and W₃ were remunerative and the best treatment combination among all others to sustain both soil and crop productivity in this region. Full article